Why ghost system after the sound card drivers installed, or no voice? ?

The unit dell brand machine, OPTIPLEX GX280 model.
Depressing dead.
Device Manager sound field that mistake did not prompt exclamation mark.
Official from the dell network to download this type of sound card driver installation or after No,
the how do we solve this??
Thank you!

Tray in the lower right corner of the small speaker icon you have to enter Safe Mode Device Manager to see if there is a conflict here? some sound card Was the original driver in the Control Panel – Add or Remove Programs in complete it.Some of this may sound card installed:Update Driver, “from the list or specified location of the installation” – “Do not search, I have to choose to install Driver, “and then point” from the installation disk “and point to the installation path you download the driver to do so.(INF file must be the kind of ah) recommended check the sound card and speakers to see whether there is a loose interface, and Speaker is working correctly, if the problem persists, the problem is caused by damage to the sound card, sound card recommended replacement.1.Each sound card has a different drive system could not drive!
2.You have installed Impact on you! Is inserted behind the wrong hole! You look like, is there a patch, if there is to be able to install the patch, not to re-install the driver.